The CO2 system I purchased uses a PH controller to regulate CO2. It was said to maintain a consistant CO2 levels. I'm concerned I may not dose enough CO2 with this system as the PH using ADA aquasoil will already lower PH, so if the PH controller isn't reading a PH level above the preset (i'm thinking of trying to keep a PH level around 6.5-6.7) it will not tell the solenoid to bubble CO2. The system is sold by aquariumplants.com. Anyone have any comments? And normally would dosing high levels of CO2 reduce PH and to what extent?